The invention relates to an electric connection, and particularly to an electric connection according to the preamble of claim 1, which allows a low-inductance connection between two or more electric parts. The invention also relates to an electric component according to the preamble of claim 9, which allows implementing the connection of the invention. The connection and the electric component are particularly applicable to the intermediate circuit of a frequency converter and to other corresponding connections.
The electric circuit of modern high-frequency transistor intermediate circuits must be as low-inductance as possible so that quick voltage variations do not cause interference to the operation of the transistors connected to this intermediate circuit. In connection with a frequency converter, an intermediate circuit comprises, in a known manner, voltage busbars of the intermediate circuit as well as capacitors and switch components connected to it, such as IGB transistors. Other corresponding devices in which the aim is low inductance include inverters, welding devices, UPS devices, various power sources, power coefficient corrective circuits, motor soft starters and control devices of induction furnaces.
With regard to the intermediate circuit, component manufacturers aim at making the internal connections of their component as low-inductance as possible. Some component manufacturers give the components they manufacture an inductance and resistance value, on the basis of which it is possible to determine for the component a switching frequency limit value with which the component still functions. The components are generally connected externally, depending on the magnitude of the current and the power to be transmitted, either by soldering on a circuit board or with a screw connection to a busbar system.
Publications U.S. Pat. No. 6,259,617, EP1445853 and U.S. Pat. No. 5,132,896 disclose intermediate circuit arrangements with which the aim is low intermediate circuit inductance. In all of these publications, it has been noted that, generally speaking, a low-inductance busbar system has been achieved by positioning the plus and minus current paths of the intermediate circuit on top of each other as symmetrically as possible. The problem of the publications is, however, that the connection structures between busbar systems and components generate undesired inductance for the current path of the intermediate circuit.